Centering and orientation apparatus

ABSTRACT

An apparatus for centering and orienting article comprising a centering body having a bore extending therethrough, a plurality of support members extending from the upper end of the centering body, an arm pivotally attached between two adjacent support members, a rod received in the bore having slidable and rotatable movement; a centering base attached on top of the rod which include the article holding space at the center and a plurality of slots extending from the periphery towards the center of the centering base. A centering finger is slidably attached to each slots of the base. When the rod is extended upwards it engages with the arm which in effect moves the centering finger away from the center of article placement area; and when rod is lowered and disengages with the arm to revert back to the original position and orientation means provided to rotate the article.

FIELD OF INVENTION

The present invention relates to an apparatus for centering andorienting article such as integrated circuits or the likes.

BACKGROUND OF THE INVENTION

In the semiconductor manufacturing industry for producing IntegratedCircuits, there are many processes involved in doing so and one of theprocess which is important is the testing of parts before packaging(packing IC or to complete IC).

For this typically a dedicated apparatus is used. Because the toleranceinvolved in placement of a chip into a tester is very small, positioningand placement accuracy is important. The tester is typically integratedwith a material-handling machine. The material-handling machine handlesthe unloading of work units from input unit trays and the transferringof units through pick-and-place heads to the final packaging medium,with the testing process in between.

To achieve placement and positioning accuracy in the testing cavity,typically a jig is used to reposition the work unit at the pickup headbefore placement into the testing cavity. This significantly reduces theprobability of unit misalignment in the testing cavity. However, passivecentering of units in this manner is less reliable thus the need for amore efficient alternative.

In addition, certain processes integrated with the material-handlingmachine, such as vision inspection processes or more prominently thetesting processes, typically require the unit to be orientated in acertain direction. Because not all units in the input unit tray may beorientated in the desired direction, material-handling machinesincorporate a separate module for the reorientation process as well.This additional module adds to the material cost of the machine.

A typical apparatus according to prior art is shown in FIG. 10 where therotating and centering apparatus is of two separate apparatus. Thepresent invitation is an effective integration between these twoapparatus.

The present invention incorporates both the centering and thereorientation processes into one compact module and have filed anotherapplication for this. The invention reduces material cost and providesfor better utilisation of space in the material-handling machine. Forflexibility of application, the invention also incorporates a supportstructure that enables adjustments in the z-axis. The modularity of theinvention enables cross-machine application without the need forredesign.

However, the first embodiment of the present invention has onedisadvantage. When a chip is not accurately placed at the receiving partof the invention, during the process of centering and orientating thechip, there is a possibility of damaging the chip. Therefore a secondembodiment of the present invention is aimed at overcoming the problemfaced by the first embodiment of the invention.

SUMMARY OF THE INVENTION

A first embodiment of the apparatus for centering and orienting articlessuch as integrated circuits or the like comprising a centering bodyhaving a plurality of support members at the upper end of said centeringbody with a bore extending therethrough and a hollowed shaft coaxialwith said bore where said hollowed shaft is telescopically connected toa rod providing slidable and rotatable movement to said rod, a fingerpedestal attached to an upper end of said rod and placed within saidcentering body; an arm pivotally attached between each two adjacentsupport members, a centering base mounted at the top of said supportmembers, said centering base includes an article holding space at thecenter and a plurality of slots extending from the periphery towards thecenter of said centering base, an orientation means attached to said rodto rotate said article holding space, and a centering finger slidablyattached to said each slots of the centering base, wherein when said rodis extended upwards it engages and pivots said arm which in effect movessaid centering finger away from the center of said article holding spaceand when said rod is lowered downwards it disengages and pivots said armrevert back to the original position moving said article into placeaccordingly.

A second embodiment of the apparatus for centering and orientingarticles such as integrated circuits or the like comprising a centeringbody having a plurality of support members at the upper end of saidcentering body with a bore extending therethrough and a hollowed shaftcoaxial with said bore where said hollowed shaft is telescopicallyconnected to a rod providing slidable and rotatable movement to saidrod, a finger pedestal having a pedestal attachment attached to an upperend of said rod and placed within said centering body, an arm pivotallyattached between each two adjacent support members, a centering basemounted at the top of said support members, said centering base includesan article holding space at the center and a plurality of slotsextending from the periphery towards the center of said centering base,an orientation means attached to said rod to rotate said article holdingspace; and a centering finger slidably attached to said each slots ofthe centering base, wherein when said rod is extended upwards it engagesand pivots a first pair of arms which is mounted in between saidpedestal attachment and said finger pedestal which in effect moves afirst pair of centering fingers away from the center of said articleholding space and when said rod is lowered downwards it disengages andpivots a second pair of arms to revert back to the original positionmoving said article into place accordingly.

BRIEF DESCRIPTION OF THE DRAWINGS

Descriptions of the functional and physical aspects of the invention inthe proceeding text will become more apparent with reference to thefollowing drawings.

FIG. 1 is an isometric view assembly drawing of the centering module ofthe present invention.

FIG. 2 is an exploded assembly view of the mechanism involved in thecentering process of the present invention.

FIG. 3 is a cross sectional view of the partial assembly shown in FIG.2.

FIG. 4 is a cross sectional view showing the retraction of centeringfingers.

FIG. 5 is a cross sectional view showing the extension of centeringfingers.

FIG. 6 is an illustration of the orientating mechanism.

FIG. 7 is an exploded view of the centering and orienting apparatus ofthe second embodiment of the present invention.

FIG. 8 shows a cross sectional view of the centering and orientingapparatus of FIG. 7 with the centering finger moved in outward radialdirection.

FIG. 9 shows a cross sectional view of the centering and orientingapparatus of FIG. 7 with the centering finger moved in inward radialdirection.

FIG. 10 is front perspective view of the prior art of the presentinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a centering and orientating module of the presentinvention. The top section of the support structure consisting of amounting plate and support bar connected through a pair of polygonalplates which is adjustable relative to the bottom support plate. A pairof screws inserted through threaded holes in the support bar rests onthe upward facing surface of the bottom support plate's lateral walls. Amotor (63) and a bearing housing are attached to the support structure.

FIG. 2 shows a partial assembly of the centering mechanism of thepresent invention. As a cylinder (17) extends, it exerts an upward forceon a clamping screw (not shown) that is connected to a rod (20). Thisrod (20) passes through two slide bushes (21) which is contained withina hollowed shaft (18) of a centering body (22). The centering body (22)includes a finger like support members (12) at the upper end of thecentering body (22) and a bore extending therethrough. The hollowedshaft (18) is attached at the bottom end of the centering body (22). Theslide bushes (21) reduce dynamic friction to provide for a smoothtransition of the rod (20). The upper end of the rod (20) is fastened toa finger pedestal (23). Preferably four arms (24) are each pivoted atthe elbow between a pair support members (12) of the centering body(22). A first end (24 a) of each arm (24) is inserted within a cavity(26) of the finger pedestal (23). A second end (24 b) of each arm (24)is mated with a U-shaped section of a finger holder (27). These holders(27) are inserted into a plurality of slots (28) provided on a centeringbase (29), which is mounted to the centering body (22). A finger (30) isattached to the finger holder (27) to provide the required surface forclamping and gripping.

The cross sectional view of the centering mechanism is shown in FIG. 3.A compression spring (31) is located within the centering body (22).When the cylinder (17) extends and actuates the rod (20), thecompression spring (31) is compressed. When the force exerted by thecylinder (17) is removed, the compression spring (31) expands pushingthe rod (20) back down to its initial position.

FIG. 4 is an illustration of an instant when the fingers (30) areretracted. As the finger pedestal (23) moves upwards due to the upwardmovement of the rod (20), the inner surface of a lower flange (40) ofthe finger pedestal (23) pushes against the section of the first end (24a) of the pivoted arm (24) within the cavity (26) of the finger pedestal(23). As the arm (24) is pivoted, the upward force applied causes thearm (24) to rotate centered at the pivot point (42). This in turn causesthe second end (24 b) of the arm (24) mated with the finger holder (27)to exert a force on an outer wall (43) of the U-shaped section of thefinger holder (27), which results in the outward radial movement of thefinger (30).

The illustration of an instant when the fingers are extended is shown inFIG. 5. As the finger pedestal (23) moves downwards due to the downwardmovement of the rod (20), the inner surface of an upper flange (50) ofthe finger pedestal (23) pushes against the section of the first end (24a) of the arm (24) within the cavity (26) of the finger pedestal (23).As the arm (24) is pivoted, the force applied causes the arm (24) torotate centered at the pivot point (42). This is turn causes the secondend (24 b) of the arm (24) mated with the finger holder (27) to exert aforce on an inner wall (51) of the U-shaped section of the finger holder(27), which results in the inward radial movement of the finger (30).

FIG. 6 is an illustration of the orientating mechanism. The mid portionof the centering body (22) is coupled to a pulley (60) that is connectedwith a belt (61) to another pulley (62) that is driven by the motor(63). The rotating motion on the pulleys (61, 62) will cause thecentering body (22) to rotate together with other correspondingcomponents within the centering mechanism except for the rod (20), (notshown in FIG. 6 but evident in preceding illustrations) and the fingerpedestal (23), (not shown in FIG. 6 but evident in precedingillustrations) that is independent of any rotational motion of thecentering body (22) as both is are not fastened to the centering body(22) and are positioned at the rotational axis of the centering body(22). The cavity (26) of the finger pedestal (23) allows the arms (24)to rotate along the cavity (26) during rotation. The bearing housing(64) with bearing (not shown) is also coupled to the centering body(22).

In a second embodiment of the present invention, the construction forall the parts of the centering and orientating mechanism is similar tothe first embodiment except for the construction of the finger pedestal(23). The centering mechanism of the second embodiment is also includesa centering body (22) having a plurality of support members (12) at theupper end and a hollowed shaft (18) at the lower end of the centeringbody (22) where a rod (20) passes therethrough. The finger pedestal (23)of the second embodiment is formed with its upper flange (50) having atransverse slot (44) for receiving a pedestal attachment (41) as shownin FIG. 7. The pedestal attachment (41) has a top plate (42) and a shaft(43) to be fitted into the finger pedestal (23) is attached inperpendicular position at the middle of the top plate (42). The pedestalattachment (41) can be lifted up from the finger pedestal (23) to apredetermined level.

The upper end of the rod (20) is fastened to the shaft (43) of thepedestal attachment (41). Preferably four arms (60) are each pivoted atthe elbow between a pair of support members (12) of the centering body(22). A first end (24 a) of each arm (60) is inserted within a cavity(26) of the finger pedestal (23). A second end (24 b) of each arm (60)is mated with a U-shaped section of a finger holder (27). A centeringfinger (30) is attached to the finger holder (27) to provide therequired surface for clamping and gripping.

In this embodiment, the second end (24 b) of a first pair of opposingarms (60 a) is engaged with an inner surface of the top plate (42) ofthe pedestal attachment (41). As the pedestal attachment (41) movesupwards due to the upward movement of the rod (20), the inner surface ofthe top plate (42) is lifted up leaving a gap for the opposing arms (60a) to be pivoted at its elbow within the cavity (26) of the fingerpedestal (23). As the opposing arms (60 a) are pivoted, the outwardforce of the second arm (24 b) will cause the opposing finger holders(27 a) which are attached with the second arm (24 b) moved in theoutward radial movements from the centering base (29) as shown in FIG.8.

As the rod (20) moves further upwards, the finger pedestal (23) will bepushed in upward movements till the inner surface of a lower flange (40)of the finger pedestal (23) pushes against the section of the first end(24 a) of the other pair of opposing arms (60 b) within the cavity (26)of the finger pedestal (23). The other opposing finger holders (27 b)will then moved in outward radial movements from the centering base(29).

As the rod (20) moves downwards, the pedestal attachment (41) will bepulled downwardly with the inner surface (41) of the top plate (42)pushes against the section of the first end (24 a) of the first pair ofopposing arms (60 a) within the cavity (26) of the finger pedestal (23).As the first pair of opposing arms (60 a) is pivoted, the force appliedcauses the arm (60 a) to rotate centered at the pivot point (42). Thiswill cause the opposing finger holders (27 a) which are attached withthe second arm (24 b) moved in the inward radial movements to thecentering base (29) as shown in FIG. 9.

As the rod (20) moves further downwards, the finger pedestal (23) willbe pulled in downward movements till the inner surface of the lowerflange (40) of the finger pedestal (23) pushes against the section ofthe first end (24 a) of the second pair of opposing arms (60 b) withinthe cavity (26) of the finger pedestal (23). The other pair of opposingfinger holders (27 b) will then moved in inward radial movements to thecentering base (29).

With these arrangements, the first opposing finger holders (61 a) willbe first moved in outward radial movements when the rod (20) is movedupwardly, and inward radial movements when the rod (20) is moveddownwardly. Further upward movements of the rod (20), will then move thesecond opposing finger holders (61 b) in outward radial movements andalso further downward movements of the rod (20), will then move thesecond opposing finger holders (61 b) in inward radial movements. Thiswill prevents the possibility of damaging the chip, when the chip is notaccurately placed at the receiving part of the invention, during theprocess of centering and orientating the chip.

While the preferred embodiments of the present invention and theiradvantages have been disclosed in the above detailed description, theinvention is not limited thereto but only by the spirit and scope of theappended claims.

1. An apparatus for centering and orienting articles such as integratedcircuits or the like comprising; a centering body having a plurality ofsupport members at the upper end of said centering body with a boreextending therethrough and a hollowed shaft coaxial with said bore wheresaid hollowed shaft is telescopically connected to a rod providingslidable and rotatable movement to said rod; a finger pedestal attachedto an upper end of said rod and placed within said centering body; anarm pivotally attached between each two adjacent support members; acentering base mounted at the top of said support members, saidcentering base includes an article holding space at the center and aplurality of slots extending from the periphery towards the center ofsaid centering base; an orientation means attached to said rod to rotatesaid article holding space; and a centering finger slidably attached tosaid each slots of the centering base, wherein when said rod is extendedupwards it engages and pivots said arm which in effect moves saidcentering finger away from the center of said article holding space andwhen said rod is lowered downwards it disengages and pivots said armrevert back to the original position moving said article into placeaccordingly.
 2. The apparatus for centering and orienting articles asclaimed in claim 1, wherein said finger pedestal includes an upperflange and a lower flange, with a cavity formed therebetween.
 3. Theapparatus for centering and orienting articles as claimed in claim 1,wherein said centering finger is slidably attached to said each slots ofthe centering base by a finger holder.
 4. The apparatus for centeringand orienting articles as claimed in claim 3, wherein said finger holderincludes a longitudinal aperture on the top surface for receiving saidcentering finger and a U-shaped section formed by an outer wallvertically fixed at the edge and an inner wall vertically fixed atsubstantially middle of the bottom surface of said finger holder.
 5. Theapparatus for centering and orienting articles as claimed in claim 1,wherein said arm includes a first end which is inserted within saidcavity of the finger pedestal and a second end which is mated with saidU-shaped section of said finger holder.
 6. The apparatus for centeringand orienting articles as claimed in claim 1, wherein said apparatus hasfour arms pivotally attached between each two adjacent support members.7. The apparatus for centering and orienting articles as claimed inclaim 1, wherein said orientation means includes a pulley coupled tosaid centering body, said pulley connected with a belt to another pulleythat is driven by a motor to translate the rotational movement of saidmotor to rotate said centering body.
 8. The apparatus for centering andorienting articles as claimed in claim 7, wherein said centering body ismounted with a compression spring within said hollowed shaft of thecentering body.
 9. The apparatus for centering and orienting articles asclaimed in claim 8, wherein said centering body is further attached witha cylinder for extending and actuating said rod.
 10. An apparatus forcentering and orienting articles such as integrated circuits or the likecomprising; a centering body having a plurality of support members atthe upper end of said centering body with a bore extending therethroughand a hollowed shaft coaxial with said bore where said hollowed shaft istelescopically connected to a rod providing slidable and rotatablemovement to said rod; a finger pedestal having a pedestal attachmentattached to an upper end of said rod and placed within said centeringbody; an arm pivotally attached between each two adjacent supportmembers; a centering base mounted at the top of said support members,said centering base includes an article holding space at the center anda plurality of slots extending from the periphery towards the center ofsaid centering base; an orientation means attached to said rod to rotatesaid article holding space; and a centering finger slidably attached tosaid each slots of the centering base, wherein when said rod is extendedupwards it engages and pivots a first pair of arms which is mounted inbetween said pedestal attachment and said finger pedestal which ineffect moves a first pair of centering fingers away from the center ofsaid article holding space and when said rod is lowered downwards itdisengages and pivots a second pair of arms to revert back to theoriginal position moving said article into place accordingly.
 11. Theapparatus for centering and orienting articles as claimed in claim 10,wherein said finger pedestal is formed with an upper flange having atransverse slot for receiving said pedestal attachment.
 12. Theapparatus for centering and orienting articles as claimed in claim 10,wherein said pedestal attachment has a top plate and a shaft to befitted into said finger pedestal, whereby said pedestal attachment canbe lifted up from said finger pedestal to a predetermined level.
 13. Theapparatus for centering and orienting articles as claimed in claim 10,wherein said apparatus includes a second pair of arms with each armhaving a first end inserted within a cavity of said finger pedestal anda second end mated with a U-shaped section of a finger holder.
 14. Theapparatus for centering and orienting articles as claimed in claim 13,wherein said second pair of arms is arranged to move in upward movementswhen said rod is moved further upwards and thus moves a second pair ofcentering fingers away from the center of said article holding space andto move in downward movements when said rod is moved further downwardsand thus said second pair of centering fingers to revert back to thecenter of said article holding space.